Re: [rtcweb] confirming sense of the room: mti codec

David Singer <> Fri, 12 December 2014 23:42 UTC

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From: David Singer <>
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Date: Fri, 12 Dec 2014 15:42:32 -0800
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Subject: Re: [rtcweb] confirming sense of the room: mti codec
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> On Dec 12, 2014, at 11:13 , Gaelle Martin-Cocher <> wrote:
> Mandatory codec agility is even more important than specific mandatory codecs, but it may take the latter to force the former.
> [GMC] generally agree.  There is quite a few more options to the above one: Shall implement at least two codecs, one is a defined MTI, the other if up to you (or is in a list of recommended codecs). The second codec can be a future looking codec. Other option: browser and non-browser do not have the same number of codecs to implement. A third option is an asymmetry in the number of decoders and encoders.

Yes, indeed.  If your goal is to make sure everyone can negotiate, we don’t have to say what over, as long as the support is for more than one.

We could also split (as I said before) transmit and receive.  Encoders are harder to do well than decoders, generally. If everyone can decode multiple codecs, they only need to be able to encode one. This also exercises negotiation.

David Singer
Manager, Software Standards, Apple Inc.